The European Union announced Saturday it had launched legal action against Poland’s rightwing government over a new law that it fears will erode judicial independence.

The action escalates EU pressure on Warsaw over what Brussels sees as a growing threat, not just to democratic standards in Poland but across the 28-nation bloc.

“The European Commission launched an infringement procedure against Poland by sending a letter of formal notice,” the EU’s powerful executive said.

It was sent after Poland published the law reorganising its ordinary courts on Friday.

The EU statement said Warsaw had one month to reply to the Commission letter, which “raises concerns that… the independence of Polish courts will be undermined.”

The action eventually could lead to Poland being hauled before the bloc’s highest court, the European Court of Justice, and possibly fined.

The Commission has also warned of even tougher measures if the governing Law and Justice Party (PiS), which has raised EU concerns since winning the Polish elections in late 2015, forges ahead with deeper court reforms.

EU ‘reversal obligatory’

In Warsaw, Polish President Andrzej Duda’s chief of staff Krzysztof Szczerski warned on Saturday that the Commission had “entered a path that leads nowhere,” saying organisation of the courts was the sovereign preserve of member states.

“At a certain point, a reversal will be obligatory” for the Commission, which will face “increasingly high” costs each step it takes, Szczerski told PAP news agency.

Poland’s deputy foreign minister for European affairs, Konrad Szymanski, said the new law carried proper guarantees and the EU action was “unfounded.”

The EU move had been expected after Duda on Tuesday signed into law a measure allowing the justice minister to unilaterally replace the chief justices of common courts, which rank below the Supreme Court.

However, Duda, a former PiS party member who turned independent, stunned the government when he vetoed another bill that would have reinforced political control over the paramount court.

He also vetoed a bill allowing parliament to choose members of a body designed to protect the independence of the courts.

The Commission said the threat to judicial independence came from the Polish justice minister getting “discretionary power to prolong the mandate of judges who have reached retirement age as well as to dismiss and appoint court presidents.”

Other concerns, it said, include “discrimination on the basis of gender” by setting the retirement age at 60 for female judges and at 65 for their male counterparts.

Timmermans also sent a letter on Friday to Poland’s Foreign Minister Witold Waszczykowski and Justice Minister Zbigniew Ziobro saying the “Commission’s hand is still extended” as he invited them to Brussels to relaunch a long drawn-out dialogue on the judiciary reforms.

The legal reforms have triggered mass street protests in Poland and raised fears for the rule of law in one of the EU’s leading eastern former communist states.

Brussels and Warsaw have been at loggerheads ever since PiS announced reforms to Poland’s constitutional court after coming to power in late 2015.

EU Justice Commissioner Vera Jourova has expressed fears the “whole EU system of mutual recognition of court decisions” could be undermined if Polish judicial independence were undermined.